/Engine/Plugins/VirtualProduction/Takes/Source/TakesCore/Public/TakeRecorderSource.h
If the source is Valid and ready to be recorded. Tells the Take Recorder that it's really going to record. Note that PreRecord/StartRecord may still get called on the source even if not Valid. This is used mainly so we only Start Recording if we have more than one Valid Source.
virtual bool IsValid() const